You probably need it. You still need to talk about it unless you are the boss - and that's not unique to the IT industry. There's other employees that might need a vacation, that might have a sick child or other things to take care off and it's just a basic fact of corporate life that it's mostly impossible that the whole company goes on vacation at the same time. So the manager must balance on who needs the vacation most, who had the first pick last time etc. So you either talk about that and maybe accept a compromise or you don't go. It's as simple as that.

> Personal time wins, and work can wait, always.

Think: Small company, important Customer who already has TV adverts on air with the release date. Project hits a roadblock no one anticipated, is a couple of days late. You can still make it if you put in extra hours, but won't make it if you prefer your personal time. Customer threatens to sue for a sum that will make the company go bust. What are you going to do? Stick to "work can wait" and look for a new job, make all your colleagues look for a new job?